{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-64541",
  "modified": "2026-10-07T17:22:01Z",
  "upstream": [
    "CVE-2026-64541"
  ],
  "published": "2026-07-27T20:10:44Z",
  "summary": "net/smc: fix UAF in smc_cdc_rx_handler() by pinning the socket",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: fix UAF in smc_cdc_rx_handler() by pinning the socket\n\nsmc_cdc_rx_handler() looks up the connection by token under the link\ngroup's conns_lock, drops the lock, and then dereferences conn and the\nsmc_sock derived from it, ending in sock_hold(&smc->sk) inside\nsmc_cdc_msg_recv(). No reference is held across the lock release.\n\nThe only reference pinning the socket while the connection is\ndiscoverable in the link group is taken in smc_lgr_register_conn()\n(sock_hold) and dropped in __smc_lgr_unregister_conn() (sock_put), both\nunder conns_lock. Once the handler drops conns_lock, a concurrent\nclose() -> smc_release() -> smc_conn_free() -> smc_lgr_unregister_conn()\ncan drop that reference and free the smc_sock, so the handler's later\nsock_hold() runs on freed memory:\n\n  WARNING: lib/refcount.c:25 at refcount_warn_saturate\n  Workqueue: rxe_wq do_work\n   refcount_warn_saturate (lib/refcount.c:25)\n   smc_cdc_msg_recv (net/smc/smc_cdc.c:430)\n   smc_cdc_rx_handler (net/smc/smc_cdc.c:502)\n   smc_wr_rx_tasklet_fn (net/smc/smc_wr.c:445)\n   tasklet_action_common (kernel/softirq.c:938)\n   handle_softirqs (kernel/softirq.c:622)\n  Kernel panic - not syncing: panic_on_warn set\n\nOnly SMC-R is affected. The SMC-D receive tasklet is stopped by\ntasklet_kill(&conn->rx_tsklet) in smc_conn_free() before the connection\nis unregistered, so it cannot run concurrently with the free.\n\nTake the socket reference while still holding conns_lock, so the\nregistration reference can no longer be the last one, and drop it once\nthe handler is done.",
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.1.47-1+rpt4"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-2712",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v6",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7l",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v8",
            "binary_version": "1:6.1.47-1+rpt4"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.1.47-1+rpt4": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.178",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-64541"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/8de4f665d0febfb92803dece377791a563fc7041"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/8145b432136285e01091815b48ceb2dae261f262"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/1951bffbc6493ec34cff3956b29d4bc6606904a6"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/647b19e5cc145a2f1f685ae8ff3805a17356888c"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/472e9d7c0d5b03be3ff91ff941f57da822b031bc"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/3bfb96d9bc6a7ed0b99c7db329cc2e22a28d84bb"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/ce5aa8084329351086894aa34d77e40301d5bd3d"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/9d160b35cc34a2ba8229d07651468a7848325135"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-08-17T05:24:08Z"
  }
}